King County Setting Example With Earthquake Debris Recycling

The 7.2 Magnitude earthquake that rattled Seattle and Western Washington ten years ago, caused widespread damage to the built environment. Thousands of commercial and residential buildings, bridges, port infrastructure and much more were completely or partially damaged. An estimated 15 million tons of debris (1.5 million truck loads) were scattered throughout King County. Most of this debris was comprised of concrete, brick and construction materials, as well as hazardous materials, appliances, automobiles, and other items. Nearly all of the streets and pedestrian pathways throughout the county had various types of debris that restricted mobility.

This story is a work of fiction, including all names and quotes, written by WWU DRR students for public education purposes. Site design by Dr. Scott Miles.

In order for businesses, the economy and the community to get back to a functional status, removing this debris was critical. The government agencies and contractors involved in cleaning up the debris took action immediately after the quake. Considering the colossal amount of debris and the wide range of materials within it, a specific plan on how and where the debris would be handled was the first priority in regaining the region’s functionality.

King County’s Office of Emergency Management (KCOEM) had fortunately prepared for such event to occur. Their disaster debris management plan included facets of the National Incident Management System (NIMS) and the Incident Command System (ICS).Upon the acceptance of King County declaring a state of emergency, KCOEM initiated its plan. Conceptual operational strategies were initiated, multi-jurisdictional and private sector legal contracts were signed, dumpsite locations were designated and a private and public list of employable heavy equipment was utilized. In other words, all available resources were utilized and operations began.

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Debris piled on the street from 2011 Japan earthquake

Japan faced a similar, but more difficult situation aftermath of the 2011 earthquake and subsequent tsunami. A large majority of the debris was generated from the tsunami alone. Nearly 23 million tons of debris was produced throughout the entire region making it one of most challenging disaster debris management operations experienced by mankind. Local cities and municipalities, along with help from the national government, dealt with the debris cleanup through sound pre-planning, collaboration and execution. Two years after the disaster, most of the loose debris from the impacted areas had been collected and moved to interim storage locations and then segregated into categories. Due to the sheer volume of debris and limited land, the real challenge Japan had was disposing of and recycling the disaster debris.

 

Today in King County,  the unfamiliar eye would not see any left over piles of debris or residual material scattered across the landscape. What one would see is that Harbor Island is rebuilt and filled in, the construction of a permanent SR-520 land bridge is well underway and one of the most progressive metropolitan recycling operations in the country is up and running.

As Johann Burgen, the spokesman for King County’s Solid Waste Division mentioned, “ We as team of thousands have not only removed the debris from around the county, helping the region to breathe again, if you will, but we recycled and re-purposed nearly 80 percent of that material for use in infrastructure projects, both big and small.”

Burgen also mentioned that prior to the quake, the Solid Waste Division had mutual aid agreements with all cities throughout King County except with the City of Seattle and Milton, which had their own waste management departments. Though, given the status of our county and state after the earthquake both cities joined the countywide organization. The Solid Waste Division has remained a countywide waste management conglomerate ever since. However, a restructuring of King County’s solid waste management is likely to occur in the coming years now that the operation of processing, handling and transporting the debris generated from the quake is nearing its end. 

During the initial efforts put forth in removing the debris, KCOEM set goals and publicly shared its strategic plan on managing the debris. One of the first goals set was to do as much of the debris processing and sorting onsite. All of the debris inside and outside of buildings were piled together based on neighborhoods. For example there were hundreds of localized debris sorting sites within the City of Seattle itself, such as in,  Capital Hill, Queen Anne, Beacon Hill, West Seattle, Magnolia and the International District. This tactic was employed throughout the entire county, but varied in intensity depending on the building and population densities of each region.

By localizing the debris management, various crews could sort and process the material faster and in a more effective manner.

As stated in one of KCOEM first press releases after the earthquake, “… diverting debris into specific neighborhood sites will enables King County Department of Transportation and the Washington Department of Transportation (WSDOT) to repair and reopen high traffic routes as soon as possible. Fleets of heavy equipment and hand crews will occupy these sites and sort the debris by their chemical makeup and recyclability. We ask for your patience and understanding of the excess noise generated from the concrete crushers, excavators and tractor trucks during daylight hours.”

This initial phase of the localized sorting and processing of the debris took approximately 11 months to complete throughout the County.

King County’s Disaster Debris Management Plan called for the county to use two main methods for debris reduction: crushing/grinding and recycling. Crushing and grinding can reduce the volume of debris up to 75 percent. A high percentage of the disaster debris came from concrete, brick and construction materials so this method was useful for priming the debris for reuse in projects around the county.

Equipment used to remove debris

Equipment used to remove debris

Recycling the debris was not only good for the environment but it made financial sense. Included within the Debris Management Plan, possible end-use products were determined and potential market demands for each product was analyzed and plausible product buyers were identified. This made for a more rapid cleanup process.

As crews worked their way through the county, the material was dispatched to varying locations based on recyclability. The 10 pre-existing waste management transfer stations, the hazardous waste collection facilities and the Cedar Hills Regional landfill within King County were utilized to further sort and process the debris.Prior to the event, King Counties Cedar Hill Landfill handles just over 800,000 tons of garbage per year.

 

During the first 24 months of removing, sorting and processing the debris, King County government strongly supported trying to handle and recycle as much of the debris as possible and done within the state. Officials were confident that the resources available within the state were sufficient to handle King County’s debris removal and recycling needs.

However, as the recycling and sorting facilities were inundated with an array of hazardous materials (cleaning products, motor oils, asbestos, etc.) and white goods (households appliances – refrigerators, hot water tanks, etc.), the various facilities’ capacities became overwhelmed. Hundreds of thousands of household and commercial appliances were piled up on the grounds of these facilities, which posed public and environmental health concerns.  There was a clear demand for external aid. In addition, engineering and technical assistance was needed on how to recycle the estimated 28 million cubic yards (~15 million tons) of these materials and the crushed concrete.

As part of the U.S Department of Homeland Security’s National Response Framework, Emergency Support Function (ESF) #3 Public Works and Engineering and National Disaster Recovery Framework were utilized. The support that the frameworks and organizations provided was critical in successfully achieving the overall debris cleanup operation. The frameworks facilitated additional access to disaster waste management expertise, environmental engineering consultations and funding.

Upon receiving federal aid, a series of ambitious goals and strategies for the debris removal operations were adopted. These goals incorporated similar goals and strategies of King Counties’ DOT, WSDOT and the Port of Seattle’s reconstruction projects that existed prior to the quake.

As noted in other news articles and reports regarding the infrastructure damage from the earthquake, Seattle’s 400-acre Harbor Island suffered significant liquefaction, experiencing up to 5 feet of land subsidence in some areas. Prior to federal support, there were 12.5 millions of yards of crushed concrete and masonry material piled up within King County’s transfer sites. Throughout the past few years, a portion of that material  was imported and used to infill portions of the subsided Harbor Island. Relative to pre-quake capacity, Harbor Island is fully functional and a serves as a multi-purpose marina, port and maritime industrial district.

At the time of the earthquake, State Route 520 floating bridge’s  was uncompleted and its land anchoring structures experienced notable damage. Coinciding with WSDOT’s goals the remainder of the bulk and crushed concrete not used for the Harbor Island Project has been used to fill sections of the State Route 520 land bridge.

Prior to the earthquake, State Route 520 was mid-way through a major reconstruction project. The NRF and NDRF supplied engineering consultation on how to reuse reclaimed concrete material in the completion of the highway project. There was enough of the concrete material to  reduce this total floating distance of the bridge by one-half.  Because of this accomplishment, SR-520 has had a significant decrease in construction costs and by current projections will have reduced future maintenance costs.

Last Months WSDOT press release, states that the SR-520 land and floating bridge project is estimated to be completed in the summer of 2025. The greatest benefit to the users of the bridge, is that with the reduced construction and maintenance costs achieved from reusing the earthquake debris, the SR-520 bridge will be un-tolled.

Throughout the past ten years, and despite the preparedness plans put together by KCOEM and the solid waste divisions, managing, sorting, processing and recycling the colossal amount of debris was no easy task. The projects and accomplishments achieved thus far can give thanks to the hard work and dedication to those involved in the cleanup.

 

Author: Anthony de Aguiar